Conventionally, for purposes of controlling the backlight of a liquid crystal display apparatus, there is a technology of controlling the lamp current of the backlight according to output information of luminance sensors pertaining to light leaked from a reflecting plate of the backlight (see, e.g., Patent document 1). In the conventional art, light leaked from the reflecting plate of a liquid crystal module is detected by sensors, and luminance control signals are outputted while monitoring this detected output so that the luminance set by the user is attained, thereby enabling maintenance of optimal display conditions.
In addition, there is a technology in which a liquid crystal panel is controlled using a look-up table in accordance with output information of color sensors pertaining to the chromaticity of the backlight, so that ΔEa*b* is minimized (see, e.g., Patent document 2). In the conventional technology, the chromaticity of the illuminating light of the liquid crystal module is detected by sensors, and display signals of the liquid crystal panel are controlled so that color differences relative to preset chromaticity information are minimized.    [Patent document 1] Japanese Patent Publication No. 3171808 (Page 3, FIG. 1)    [Patent document 2] Japanese Unexamined Patent Application, First Publication No. 2006-91235 (Page 14, FIG. 4)